From mboxrd@z Thu Jan 1 00:00:00 1970 To: 9fans@cse.psu.edu Subject: Re: [9fans] Re: moving things in a window In-Reply-To: Your message of "Thu, 28 Sep 2000 10:18:48 GMT." <39D23579.265E60B8@arl.army.mil> References: , <39D23579.265E60B8@arl.army.mil> Date: Thu, 28 Sep 2000 12:28:55 +0100 From: Theo Honohan Message-Id: Topicbox-Message-UUID: 11c78296-eac9-11e9-9e20-41e7f4b1d025 In message <39D23579.265E60B8@arl.army.mil>, "Douglas A. Gwyn" writes: > andrey mirtchovski wrote: > > ... So the mask says ``only draw where the old circle was > > but the new circle is not''. > > The final draw puts white down in those places. > > Of course, that clobbers other objects in the same (old) location. > I know of no way to do this right without taking into account all > potentially visible objects. If the hardware can help (Z-buffer, > or render a model) that's great. For hardware acceleration, it looks like you'd have to extend the draw protocol with something equivalent to GLX. I'm not sure yet whether explicit support for double buffering, on its own, would be a useful addition. (See my previous message.) Keith Packard's "render" mailing list has seen some hard-hitting discussion of these and related issues recently. http://XFree86.Org/mailman/listinfo/render